A wireless receiver receives location pilots embedded in received symbols and uses the location pilots to detect the first path for every base station the network has designated for the receiver to use in time of arrival estimation. The receiver preferably applies matching pursuit strategies to offer a robust and reliable identification of a channel impulse response's first path. The receiver may also receive and use estimation pilots as a supplement to the location pilot information in determining time of arrival. The receiver can use metrics characteristic of the channel to improve the robustness and reliability of the identification of a CIR's first path. With the first path identified, the receiver measures the time of arrival for signals from that path and the receiver determines the observed time difference of arrival (OTDOA) to respond to network requests for OTDOA and position determination measurements.

In some embodiments of the invention, OFDM symbols are transmitted as a plurality of clusters. A cluster includes a plurality of OFDM sub-carriers in frequency, over a plurality of OFDM symbol durations in time. Each cluster includes data as well as pilot information as a reference signal for channel estimation. In some embodiments, a plurality of clusters collectively occupy the available sub-carrier set in the frequency domain that is used for transmission. In some embodiments of the invention data and/or pilots are spread within each cluster using code division multiplexing (CDM). In some embodiments pilots and data are separated by distributing data on a particular number of the plurality of OFDM symbol durations and pilots on a remainder of the OFDM symbol durations. CDM spreading can be performed in time and/or frequency directions.

A wireless communication technique to improve channel estimation using pilot signals includes receiving data symbols for transmission over a wireless communication channel using multiple antenna ports, generating a plurality of scrambling sequences, each corresponding to one of the multiple antenna ports, mapping, for each antenna port, a corresponding pilot signal to time and frequency transmission resources using a corresponding scrambling sequence, multiplexing a first input from the data symbols and a second input from the mapping of the corresponding pilot signal to generate an output signal, and transmitting the output signal over a wireless communication channel.

The present technology relates to a data processing apparatus and a data processing method which can suppress the influence of multipath propagation and the Doppler shift. A data processing apparatus includes a processing unit which performs modulation processing on a physical layer frame including a preamble, which includes a modulation parameter, and one or more subframes, which include data, in which any modulation parameter can be set for each of the subframes, and the subframes are arranged in the physical layer frame collectively by subframe groups which are collections of the subframes with FFT sizes, which are same, when IFFT operation is performed on symbols included in the physical layer frame. The present technology can be applied to, for example, data transmission compliant to a broadcast standard such as ATSC 3.0.

A method and apparatus for improving channel estimation within an OFDM communication system. Channel estimation in OFDM is usually performed with the aid of pilot symbols. The pilot symbols are typically spaced in time and frequency. The set of frequencies and times at which pilot symbols are inserted is referred to as a pilot pattern. In some cases, the pilot pattern is a diagonal-shaped lattice, either regular or irregular. The method first interpolates in the direction of larger coherence (time or frequency). Using these measurements, the density of pilot symbols in the direction of faster change will be increased thereby improving channel estimation without increasing overhead. As such, the results of the first interpolating step can then be used to assist the interpolation in the dimension of smaller coherence (time or frequency).

A propagation channel estimation method is provided. In-phase and quadrature components of a propagation channel estimation value in each pilot subcarrier are separated into amplitude and phase components. A propagation channel of a data subcarrier portion existing between pilot subcarriers is estimated by phase/amplitude separation linear interpolating in each separated amplitude and phase component. A reference parameter is produced by linear interpolating a portion between pilot subcarriers on a complex plane. When quadrants on the complex plane of the interpolated phase component estimation value and the reference parameter are different, a phase connecting process to cancel a discontinuity of the phases is executed to the phase component estimation value interpolated by the phase/amplitude separation linear interpolation. When the quadrants are not different or after the phase connecting process, a complex propagation channel estimation value of the data subcarrier portion is calculated from the phase and amplitude components of the propagation channel estimation value.

Disclosed is a method, receiver, multi-receiver device, system and computer readable medium for configuring a receiver to perform multi-transmitter channel estimation for a time-varying channel. In one aspect, the method includes: wirelessly receiving at least two frames, each frame including a block of training symbols received at different points in time for a time-varying channel; estimating, for each block at a block location, a first channel coefficient of the time-varying channel, wherein the block location is the same for each block; and interpolating or extrapolating a plurality of second channel coefficients for the respective training symbols of each block based on the respective first channel coefficient.

Systems and methods are provided for a network to indicate beamforming information to user equipment (UE) for identification and measurement of reference signals. For example, a network may indicate whether all the reference signals are beamformed or not, or which reference signals are using the same transmission beamforming on the time domain, the frequency domain, or both time and frequency domains. In other embodiments, a network may indicate combining or averaging information to a UE.

The method: extracts symbols at pilot positions from the received stream of symbols, estimates noise variances at pilot positions, determines a rough channel estimation from the symbols extracted at pilot positions, determines weighting coefficients from the estimated noise variances, weights the rough channel estimation by the determined weighting coefficients, filters the weighted rough channel estimation using predetermined coefficients, at least one predetermined coefficient being different from the other predetermined coefficients, the predetermined coefficients being determined for a constant noise variance, determines normalization coefficients from the determined weighting coefficients and predetermined filter coefficients, normalizes the filtered weighted rough channel estimation using the determined normalization coefficients.

A propagation channel estimation method is provided. In-phase and quadrature components of a propagation channel estimation value in each pilot subcarrier are separated into amplitude and phase components. A propagation channel of a data subcarrier portion existing between pilot subcarriers is estimated by phase/amplitude separation linear interpolating in each separated amplitude and phase component. A reference parameter is produced by linear interpolating a portion between pilot subcarriers on a complex plane. When quadrants on the complex plane of the interpolated phase component estimation value and the reference parameter are different, a phase connecting process to cancel a discontinuity of the phases is executed to the phase component estimation value interpolated by the phase/amplitude separation linear interpolation. When the quadrants are not different or after the phase connecting process, a complex propagation channel estimation value of the data subcarrier portion is calculated from the phase and amplitude components of the propagation channel estimation value.